It’s Lacey Chabert!
It's Gretchen Wieners herself, Lacey Chabert! Miss "Sha-Bear" played Claudia Salinger in 'Party of Five' for most of the '90s before giving life to Eliza Thornberry in the animated TV series, 'The Wild Thornberrys.'
Her voicework would eventually lead her to star as Meg Griffin in the first season of 'Family Guy,' but she'd move on to star in more movies.
In 2004, she starred as Gretchen Wieners in 'Mean Girls.' While she didn't quite make the word "fetch" happen, she looked damn good on screen and helped cement Gretchen as a classic teen movie character for years to come. And hot damn, she looked fine.